Topic 6: Memory Flashcards
What is the point of long-term memory?
to acquire information from experience, maintain it overtime, and use it when relevant to guide behaviour and plan future actions
are learning and memory the same thing?
for our purposes, yes
T/F
memory occurs at least a little bit in most parts of the brain
true - some areas are more focused than others, but most parts are involved in some way
T/F memory is a chemical change, not a physical one
false - memory requires a physical change in the nervous system
what is a relatively decent analogy discussed in class that memory can be compared to? Explain.
human memory is analogous to a computer memory
- binary code ~ number & strength between neurons
- both have a short term memory that require active maintenance, and a long term, passively store memory
- differences: organization, interpretation, and access
____ & ____ between ____ are the underlying representation of all memory
number & strength between neurons
Encoding
initial creating of memory information
consolidation
continued organization and stabilization
storage
keeping information; retention
retrieval
accessing/using stored information
reconsolidation
possible reorganization and restabalization after retrieval
differences between short and long term memory
Short: - immediate recall of items in the same order (memory span) - seconds - limited capacity - sustained activation of neurons Long: - recall in any order until all (more) can be named (list learning) - minutes, hours, days, years - massive capacity - number and strength of neurons
damage to the left temporoparital lobe vs. damage to bilateral medial temporal lobes
left temporoparital lobe: deficit in list learning/LTM
bilateral medial temporal lobes: memory span/STM
dissociation
performance differs across two tasks
what are the two alternative explanations in a single dissociation of STM vs LTM?
- Parietal damage argument: there is only one system, but STM task is harder, so when the system is damaged, the STM task suffers
- Compensation argument: one system, but STM is harder, so when the system is completely damaged, the brain can compensate for the LTM task but not the STM task
if you have a single dissociation, are you demonstrating separable systems, different brain areas, or distinct cognitive processes?
NO!
double dissociation
provides evidence for separable systems that depend on different brain regions and distinct cognitive processes
about how many words can the average person hold in STM?
~7
about how many words does a person have in their vocabulary?
~ 20 000 (hard to measure though)
Implicit Memory Task
- perceptual identification (identifying word)
- damage to right occipital lobe could not perform implicit, but could perform explicit
Explicit memory task
- word recognition (ask if new or not)
- amnesia patients could not perform explicit but could perform implicit
Implicit long-term memory
- non decalrative
- no conscious awareness
- procedural, priming
- minutes, hours, days, or years
- massive (1000s of motor sequences)
- number and strength of synapses
explicit long-term memory
- declarative
- available to conscious awareness
- semantic and episodic
- minutes, hours, days, years
- massive
- number and strength of synapses
motor adaptation
- cerebral loops
- the motor perturbation task depends on spatial representation in parietal lobe
describe the study with prism glasses and what is was used for
to study motor adaptation; hand-eye coordination task by throwing darts with prism glasses on (shift visual field to the side)
- control people adapted to it, whereas those with cerebellar lesions can’t adapt
how is the cerebellum involved in motor adaptation?
forward model (uses the current position and motor comments to predict position) to predict results of motor commands - used differences between actual results and predicted results for online error correction, motor learning, and feedback control
motor sequence learning
- cortico-basal ganglia-thalamocortical loops
- serial reaction time task (random order or reporting sequence)
- dopamine signal from SNc represents prediction error
how does motor sequence learning occur depending on the basal ganglia and reinforcement learning?
- select action expected to learn to maximum reward
- perform action
- compare actual reward to expected reward (prediction error)
- use predicted error to update expectation
- repeat
how do you get prediction error?
actual reward - predicted reward
reinforcement learning
- unexpected reward generate dopamine signals from the SNc that excites the direct pathway and inhibits the indirect
- allows modification of behaviour based on reward
Cognitive Skill Learning
problem solving tasks in which subjects are required to use various cognitive skills to solve a task
amnesia vs. parkinson’s patients in an episodic memory task and a probabilistic task
amnesia patients with medial temporal lobe damage can’t complete complete an episodic memory task, whereas parkinson’s patients with basal ganglia damage could
amnesia patients with medial temporal lobe damage could complete the weather prediction task, whereas parkinson’s patients with basal ganglia damage never learned the task
damages basal ganglia impairs ____ learning, but not ____ learning.
skill learning, not declarative
Habituation (with example)
reduced response to an unchanging stimulus (e.g. touching siphon –> withdrawal of gill; repeated touch of siphon –> less withdrawal)
Pre-synaptic depressions
same action potential; reduced neurotransmitter released; smaller EPSP
Sensitization (with example)
increased response to an unchanging stimulus (e.g. touching siphon –> withdrawal of gill; shocking tail –> enhanced habituation and there is more withdrawal)
pre-synaptic facilitation
same action potential; increased neurotransmitter release; larger EPSP
Delay conditioning
a form of conditioning in which the conditioned stimulus is still ongoing when the unconditioned stimulus starts and they both terminate at the same time
Trace conditioning
a form of conditioning in which there is a brief time interval between the end of conditioned stimulus and the start of the unconditioned stimulus
what parts of the brain are associated with 1. delay conditioning, and 2. trace conditioning
- cerebellum
2. cerebellum and hippocampus
why is trace conditioning not totally non-declarative?
it requires memory trace to link CS and US; there must be some kind of memory trace in the nervous site for the CS and US relationship to be established
Fear conditioning
a form of emotional learning in which fear responses are acquired to cues that predict the occurrence of an aversive stimulus
where is the neural circuit involved in fear conditioning?
CS and US coverage in lateral nucleus of amygdala after repeated pairing of shock
perceptual priming
presenting a stimulus (prime), to someone, and at a later point, they are tested
Korsakoff’s syndrom patients
amnesia due to sever alcoholism; they improved on implicit memory day to day even though they did not remember the previous day’s training
Conceptual Priming
prime and target are the same item; thing that evokes it is conceptually related
Semantic priming
faster reaction times for related words because the first word primes the second word (in comparison to unrelated word or pseudo words - not real words)
where does perceptual priming occur?
sensory cortices
where does conceptual and semantic priming occur?
unimodal and mulitmodal assocaited cortices (e.g. anterior temporal, inferior parietal, prefrontal cortex)
